A private jet took Connor, 17, to the popular, celebrity-filled convention, where he worked the IGN Entertainment party celebrating the new Resident Evil 6 game at the Hard Rock Hotel, opening for Jermaine Dupri and RZA.

“He seemed very upbeat and he looked great,” says an onlooker. “He seemed to be having a great time performing for the crowd. Everyone totally ate it up! They were really getting into the music he was playing.”

While the younger Cruise was the center of attention in front of hundreds at the bash while performing on stage – his dad’s split from Katie Holmes has dominated the Hollywood news – he didn’t stick around for the late-night party.

“Everyone was trying to get a minute with him after the set, but he took off soon after,” says the observer.